Floor panel

ABSTRACT

A floor panel ( 1 ) provided with corresponding, mechanical locking elements ( 7, 12 ) on at least two opposed sides ( 5, 6 ) thereof, and having a core ( 4 ), a walk-on surface ( 2 ) and a bottom surface ( 3 ). In order to provide a floor panel of this type with impact sound insulation in a structurally simple and effective manner, it is suggested that at least one recess ( 13, 19 ) is provided, which extends from said bottom surface ( 3 ) into said core ( 4 ).

The present invention relates to a floor panel of rectangular shape ofthe type defined in the generic clause of claim 1.

Such a floor panel is known from EP 1 264 946. The known floor panelincludes a sound insulation in the form of at least one sound insulationlayer which is arranged on the side of the core facing the walk-onsurface. The sound insulation layer is made of a thin, soft, resilientmaterial, in particular a plastic material, and must be incorporatedinto the laminate during the production of the floor panel; this iscomparatively complicated and expensive.

WO 99/00242 shows a floor panel of rectangular shape comprising a coreof solid wood and two thinner boards which are also made of solid woodand which are arranged on the upper and the lower side of the core. Thefloor panel is sound insulated; in a first embodiment, sound insulationlayers are interposed between the core and the boards covering the coreon both sides thereof, the drawbacks being the above-described ones.

In another embodiment, the sides of the core which face the neighbouringthinner boards are provided with grooves by means of which thewood-to-wood contact area is reduced, so as to effect sound insulation.However, this arrangement also leads to a reduction of theforce-transmitting area between the wood layers; in extreme cases, thismay have the effect that, in floor areas which are frequently walked on,the vertices located between the grooves may flatten so that the floorwill slightly drop there.

In addition, the core has provided therein longitudinally extendinggrooves, which are incorporated alternately from the upper and the lowerside, said grooves extending into the core over a distance correspondingto half the thickness of said core. These grooves are provided for thepurpose of compensating the swelling and the shrinking of the wood inthe case of humidity changes so that the so-called working of the woodwill not cause distortions of the flooring. These grooves do, however,not extend up to the bottom surface, but they are covered by saidthinner boards, which act as acoustical bridges. In addition, thesolid-wood floor panels described are configured for glueing; the layersof glue extending between the panels produce a sound-insulating effectas well, so that the demands to be satisfied by an additional soundinsulation are not as high.

Finally, it is common practice to insert sound-absorbing layers of(needled) felt, plastic material, rubber or the like below the panelsduring floor laying, or said layers may be glued to the panels in thecourse of the production process; this is rather complicated andexpensive.

It is therefore the object of the present invention to provide a floorpanel with an effective impact sound insulation which is easy toproduce.

This object is achieved by a floor panel provided with corresponding,mechanical locking elements on at least two sides thereof, andcomprising a core, a walk-on surface and a bottom surface, wherein atleast one recess is provided, which extends from said bottom surfaceinto said core.

It turned out that, surprisingly enough, it is possible to achieve forfloor panels with mechanical locking systems, i.e. floor panels whichare not provided with a layer of glue between the individual panels, aneffective impact sound insulation by means of a recess extending fromthe bottom surface up to an into the core. In practical tests, it turnedout that the impact sound can be reduced significantly, e.g. by 3 dB.

Advantageous further developments of the present invention are disclosedin the subclaims.

In the following, an embodiment of the present invention will beexplained in detail making reference to the drawings in which:

FIG. 1 shows a perspective view of a floor panel according to thepresent invention,

FIG. 2 shows the section II-II according to FIG. 1,

FIG. 3 s hows the section III-III according to FIG. 1,

FIG. 4 shows part of a flooring made of the floor panels according tothe present invention, and

FIG. 5 shows part of another flooring made of other floor panelsaccording to the present invention.

FIG. 1 shows in a perspective view a first embodiment of a floor panel 1according to the present invention, comprising a walk-on surface 2 and abottom surface 3, which cannot be seen in FIG. 1 and which serves as acontact surface that rests on a floor substrate, as well as a core 4arranged between said bottom surface 3 and said walk-on surface 2.

The floor panel 1 shown represents part of a laminate floor, the walk-onsurface 2 being preferably defined by a laminate layer which isresistant to footsteps, insensitive to damage and dirt, and decorative.The core 4 is preferably made of an industrially produced wood fibrematerial, in particular an MDF/HDF board or a chipboard. The bottomsurface 3 is the bottom surface of the core 4 consisting of the materialof said core or it can be formed by a protection or compensation layer(here not shown in the drawing) which is laminated onto the core.

The floor panel 1 shown here is rectangular in shape and comparativelysmall; the width B ranges from 5 cm to 15 cm, and is preferably 8 cm,and the length L ranges from 20 cm to 80 cm, and is preferably 60 cm.The floor panel has therefore two opposed long sides 5 a and 5 b as wellas two opposed short sides 6 a and 6 b. At least the long sides 5 a, 5 bare provided with corresponding, mechanical locking elements 7 a and 7 bby means of which neighbouring floor panels can be interlocked via asnap-in connection. The locking element 7 a comprises for this purpose astrip 8 with a projection 8 a which is delimited towards the inner sideby a groove 9. The locking element 7 b includes a recess 10 forreceiving therein the strip 8, with an undercut portion 10 a forreceiving therein the projection 8 a, said recess 10 being delimitedtowards the outside by a strip 11 which is adapted to be received insaid groove 9. This allows the long sides of neighbouring floor panelsto be interlocked through a snap-in connection; in order to do so, itwill only be necessary to place the long sides of the two panels incontact with one another at an angle in such a way that the projection 8a is introduced in the recess 10, and to orient the two panelssubsequently such that they are brought into aligned, flat relationshipwith one another, whereby the projection 8 a will move into the undercutportion 10 a. The dimensions of the locking elements 7 a, 7 b, inparticular the widths b thereof, are adapted to one another in such away that the two panels cannot be displaced relative to one another in adirection parallel to the short sides 6 a.

In the embodiment shown, also the two short sides 6 a, 6 b are providedwith corresponding locking elements 12 a, 12 b; the locking element 12 acorresponds to the locking element 7 b and the locking element 12 bcorresponds, in analogy therewith, to the locking element 7 a, butwithout the projection, so that the short sides of the panels can beconnected to one another simply by pressing down, whereby the laying ofthe floor will be facilitated.

The connection via the locking elements 7 a, 7 b and 12 a, 12 b does notnecessitate an application of glue.

The floor panel 1 according to the present invention is provided with asound insulation, especially an insulation against impact sound, whichis easy to produce and nevertheless effective, said sound insulationbeing provided in the form of at least one recess 13 which extends intothe panel from the bottom surface 3 thereof, said bottom surface 3being, with the exception of said recess 13, level and flat. In theembodiment shown, sound insulation is effected by a single recess 13extending in the form of a groove from one short side 6 a continuouslyup to the other short side 6 b. The recess 13 has a depth t which isdimensioned such that said recess 13 extends from the bottom surface 3into the core 4 over a distance corresponding to one third up to onehalf of the thickness D of said core 4. The recess 13 is open and shouldalso remain open towards the bottom surface 3. If actually necessary,however, it is possible to apply a thin layer, which does not establishan acoustical bridge, to the bottom surface 3 in such a way that saidrecess 13 is covered. The recess 13 should, however, not lose its soundwave-interrupting function under any circumstances.

The recess has a width s between 1 and 10 mm and extends approximatelyin the middle between the long sides 5 a, 5 b, parallel to said longsides 5 a, 5 b and up to and into the area of the locking elements 12 a,12 b of the short sides 6 a, 6 b. From the outer strip of the lockingelement 12 a, a small connecting web 14 can remain, which will improvethe coherence.

FIG. 4 shows a part of a flooring 15 which has been produced from aplurality of floor panels 1 according to FIG. 1 to 3. FIG. 4 shows thebottom surface of the flooring 15 and an arrangement of the floor panels1 in which said respective floor panels are arranged in parallel anddisplaced by one half of their length, in the form of a regular plankflooring. As can be seen from FIG. 4, the locking elements 7 a, 7 b aswell as 12 a, 12 b of neighbouring floor panels are implemented suchthat, on the bottom surface of the flooring, grooves 16 are formedbetween the long sides of neighbouring panels and grooves 17 are formedbetween the short sides of neighbouring panels, whereas the walk-onsurfaces 2 of neighbouring panels abut on one another almost without anyintermediate gaps. This means that, with floor panels 1 having a width Bof 8 cm, longitudinally extending continuous grooves 13, 16, whichprovide effective impact sound insulation, will be formed every 4 cm. Inaddition, also the grooves 17 between neighbouring short sides serve toprovide impact sound insulation.

FIG. 5 shows a further embodiment of a flooring 18 consisting of afurther embodiment of floor panels 1′ implemented according to thepresent invention, in the form of a herringbone flooring; also said FIG.5 shows the bottom surfaces 3.

The floor panel 1′ differs from the floor panel 1 only with regard to adeviating kind of recess, the recesses provided here being a pluralityof individual, slot-shaped recesses 19 which are disposed in an in-linearrangement one after the other. As for the rest, the structural designof the floor panel 1′ corresponds to that of the floor panel 1; inparticular, the in-line arrangement of the recesses 19 is again disposedin the middle between and parallel to the long sides 5 a and 5 b andextends from one short side 6 a to the opposed short side 6 b. Also inthe case of the herringbone pattern of the flooring 18, grooves 20 areformed for impact sound insulation between the long and the short sides.

As modifications of the embodiments described and shown hereinbefore,the recesses can be varied with respect to their shape, size (depth,width, length), arrangement and number. For example, two or morecontinuous recesses can be provided for larger floor panels, or aplurality of recesses can be distributed over the bottom surfaces in theform of rows, in a diamond shape or in some other kind of arrangement.The recesses need not necessarily be arranged such that they extendparallel to the long sides, but they may also be arranged along theshort sides or at random. The recesses need not necessarily beimplemented as grooves, but they may, for example, also be implementedas notches, blind holes, incisions or the like. It is not absolutelynecessary that the floor panels are provided with locking elements onall four sides thereof; especially when the floor panels are laid in theform of a plank flooring, it may e.g. suffice to provide only the longsides with these locking elements. The shape and the mode of operationof the locking elements can be varied as well. The present invention cantherefore be used for floor panels with all kinds of commonly usedlocking elements or for floor panels that have to be glued together. Inaddition, the present invention can be used for floor panels havingother shapes and dimensions, including panels of normal size andstandard size having dimensions of 120×20 cm, or panels with miterjoints, square, hexagonal or the like. Also the material chosen for thefloor panel can be adapted to changes in the intended use. Finally, allthe embodiments of the floor panels are suitable for all commonly usedlaying patterns.

1. A floor panel (1, 1′) provided with corresponding, mechanical lockingelements (7 a, 7 b; 12 a, 12 b) on at least two sides (5 a, 5 b; 6 a, 6b) thereof, and comprising a core (4), a walk-on surface (2) extending abottom surface (3), and at least one recess (13, 19) extending from saidbottom surface (3) into said core (4).
 2. A floor panel according toclaim 1, wherein the recess (13, 19) extends into the core (4) over adistance corresponding to approximately one third up to one half of thethickness (D) of said core (4).
 3. A floor panel according to claim 1,wherein the recess (13, 18) has a width (s) of from 1 to 10 mm.
 4. Afloor panel according to claim 1, wherein the floor panel is formed of arectangular shape with short and long sides (5 a, 5 b; 6 a, 6 b), therecess (13, 18) extending continuously from one short side (6 a) to theopposite short side (6 b).
 5. A floor panel according to claim 1, andwherein a plurality of spaced-apart recesses (19) is provided.
 6. Afloor panel according to claim 5, wherein the plurality of spaced-apartrecesses (19) is arranged in at least one row extending from one shortside (6 a) to an opposite short side (6 b) of a rectangular shape.
 7. Afloor panel according to claim 1, wherein the core (4) contains a woodfiber material.
 8. A floor panel according to one claim 1, wherein thelocking elements (7, 12) are implemented such that, when one panel isjoined with a neighboring panel, a recess (16, 17) will be formed on thebottom surface (3).
 9. A floor panel according to claim 1, wherein thefloor panel is formed so that the long sides (5 a, 5 b) of a rectangularshape are each provided with corresponding, mechanical locking elements(7 a, 7 b) for locking engagement with neighboring neighbouring panels,and a groove-shaped recess (13) extends from the bottom surface (3) intothe core (4), the recess extending continuously from one short side (6a) to the opposite short side (6 b).
 10. A floor panel according toclaim 1, wherein the floor panel is formed so that the short and thelong sides (6 a, 6 b; 5 a, 5 b) of a rectangular shape are each providedwith corresponding locking elements (7 a, 7 b; 12 a, 12 b) forengagement with neighboring panels, and a plurality of spaced-apartrecesses (19) extend in an in-line arrangement from the bottom surface(3) into the core (4), the in-line arrangement extending from one shortside (6 a) to the opposite short side (6 b).
 11. A floor panel accordingto claim 1, and wherein a flooring (15, 18) is produced from a pluralityof floor panels (1, 1′).
 12. A floor panel according to claim 9, andwherein a flooring (15) is produced from a plurality of floor panels (1)being laid parallel to one another.
 13. A floor panel according to claim10, and wherein a flooring (18) is produced from a plurality of floorpanels (1′) being laid in a herringbone pattern.
 14. A floor panelaccording to claim 7, wherein the wood fiber material is MDF/HDF board.